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  <div class="section" id="database-forge-class">
<h1><a class="toc-backref" href="#id1">Database Forge Class</a><a class="headerlink" href="#database-forge-class" title="Permalink to this headline">¶</a></h1>
<p>The Database Forge Class contains methods that help you manage your
database.</p>
<div class="contents topic" id="table-of-contents">
<p class="topic-title first">Table of Contents</p>
<ul class="simple">
<li><a class="reference internal" href="#database-forge-class" id="id1">Database Forge Class</a><ul>
<li><a class="reference internal" href="#initializing-the-forge-class" id="id2">Initializing the Forge Class</a></li>
<li><a class="reference internal" href="#creating-and-dropping-databases" id="id3">Creating and Dropping Databases</a></li>
<li><a class="reference internal" href="#creating-and-dropping-tables" id="id4">Creating and Dropping Tables</a><ul>
<li><a class="reference internal" href="#adding-fields" id="id5">Adding fields</a></li>
<li><a class="reference internal" href="#adding-keys" id="id6">Adding Keys</a></li>
<li><a class="reference internal" href="#creating-a-table" id="id7">Creating a table</a></li>
<li><a class="reference internal" href="#dropping-a-table" id="id8">Dropping a table</a></li>
<li><a class="reference internal" href="#renaming-a-table" id="id9">Renaming a table</a></li>
</ul>
</li>
<li><a class="reference internal" href="#modifying-tables" id="id10">Modifying Tables</a><ul>
<li><a class="reference internal" href="#adding-a-column-to-a-table" id="id11">Adding a Column to a Table</a></li>
<li><a class="reference internal" href="#dropping-a-column-from-a-table" id="id12">Dropping a Column From a Table</a></li>
<li><a class="reference internal" href="#modifying-a-column-in-a-table" id="id13">Modifying a Column in a Table</a></li>
</ul>
</li>
<li><a class="reference internal" href="#class-reference" id="id14">Class Reference</a></li>
</ul>
</li>
</ul>
</div>
<div class="section" id="initializing-the-forge-class">
<h2><a class="toc-backref" href="#id2">Initializing the Forge Class</a><a class="headerlink" href="#initializing-the-forge-class" title="Permalink to this headline">¶</a></h2>
<div class="admonition important">
<p class="first admonition-title">Important</p>
<p class="last">In order to initialize the Forge class, your database
driver must already be running, since the forge class relies on it.</p>
</div>
<p>Load the Forge Class as follows:</p>
<div class="highlight-ci"><div class="highlight"><pre><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">load</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="p">()</span>
</pre></div>
</div>
<p>You can also pass another database object to the DB Forge loader, in case
the database you want to manage isn&#8217;t the default one:</p>
<div class="highlight-ci"><div class="highlight"><pre><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">myforge</span> <span class="o">=</span> <span class="nv">$this</span><span class="o">-&gt;</span><span class="na">load</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="p">(</span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">other_db</span><span class="p">,</span> <span class="k">TRUE</span><span class="p">);</span>
</pre></div>
</div>
<p>In the above example, we&#8217;re passing a custom database object as the first
parameter and then tell it to return the dbforge object, instead of
assigning it directly to <tt class="docutils literal"><span class="pre">$this-&gt;dbforge</span></tt>.</p>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">Both of the parameters can be used individually, just pass an empty
value as the first one if you wish to skip it.</p>
</div>
<p>Once initialized you will access the methods using the <tt class="docutils literal"><span class="pre">$this-&gt;dbforge</span></tt>
object:</p>
<div class="highlight-ci"><div class="highlight"><pre><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">some_method</span><span class="p">();</span>
</pre></div>
</div>
</div>
<div class="section" id="creating-and-dropping-databases">
<h2><a class="toc-backref" href="#id3">Creating and Dropping Databases</a><a class="headerlink" href="#creating-and-dropping-databases" title="Permalink to this headline">¶</a></h2>
<p><strong>$this-&gt;dbforge-&gt;create_database(&#8216;db_name&#8217;)</strong></p>
<p>Permits you to create the database specified in the first parameter.
Returns TRUE/FALSE based on success or failure:</p>
<div class="highlight-ci"><div class="highlight"><pre><span class="k">if</span> <span class="p">(</span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">create_database</span><span class="p">(</span><span class="s1">&#39;my_db&#39;</span><span class="p">))</span>
<span class="p">{</span>
        <span class="k">echo</span> <span class="s1">&#39;Database created!&#39;</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
<p><strong>$this-&gt;dbforge-&gt;drop_database(&#8216;db_name&#8217;)</strong></p>
<p>Permits you to drop the database specified in the first parameter.
Returns TRUE/FALSE based on success or failure:</p>
<div class="highlight-ci"><div class="highlight"><pre><span class="k">if</span> <span class="p">(</span><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">drop_database</span><span class="p">(</span><span class="s1">&#39;my_db&#39;</span><span class="p">))</span>
<span class="p">{</span>
        <span class="k">echo</span> <span class="s1">&#39;Database deleted!&#39;</span><span class="p">;</span>
<span class="p">}</span>
</pre></div>
</div>
</div>
<div class="section" id="creating-and-dropping-tables">
<h2><a class="toc-backref" href="#id4">Creating and Dropping Tables</a><a class="headerlink" href="#creating-and-dropping-tables" title="Permalink to this headline">¶</a></h2>
<p>There are several things you may wish to do when creating tables. Add
fields, add keys to the table, alter columns. CodeIgniter provides a
mechanism for this.</p>
<div class="section" id="adding-fields">
<h3><a class="toc-backref" href="#id5">Adding fields</a><a class="headerlink" href="#adding-fields" title="Permalink to this headline">¶</a></h3>
<p>Fields are created via an associative array. Within the array you must
include a &#8216;type&#8217; key that relates to the datatype of the field. For
example, INT, VARCHAR, TEXT, etc. Many datatypes (for example VARCHAR)
also require a &#8216;constraint&#8217; key.</p>
<div class="highlight-ci"><div class="highlight"><pre><span class="nv">$fields</span> <span class="o">=</span> <span class="k">array</span><span class="p">(</span>
        <span class="s1">&#39;users&#39;</span> <span class="o">=&gt;</span> <span class="k">array</span><span class="p">(</span>
                <span class="s1">&#39;type&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;VARCHAR&#39;</span><span class="p">,</span>
                <span class="s1">&#39;constraint&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;100&#39;</span><span class="p">,</span>
        <span class="p">),</span>
<span class="p">);</span>
<span class="c1">// will translate to &quot;users VARCHAR(100)&quot; when the field is added.</span>
</pre></div>
</div>
<p>Additionally, the following key/values can be used:</p>
<ul class="simple">
<li>unsigned/true : to generate &#8220;UNSIGNED&#8221; in the field definition.</li>
<li>default/value : to generate a default value in the field definition.</li>
<li>null/true : to generate &#8220;NULL&#8221; in the field definition. Without this,
the field will default to &#8220;NOT NULL&#8221;.</li>
<li>auto_increment/true : generates an auto_increment flag on the
field. Note that the field type must be a type that supports this,
such as integer.</li>
<li>unique/true : to generate a unique key for the field definition.</li>
</ul>
<div class="highlight-ci"><div class="highlight"><pre><span class="nv">$fields</span> <span class="o">=</span> <span class="k">array</span><span class="p">(</span>
        <span class="s1">&#39;blog_id&#39;</span> <span class="o">=&gt;</span> <span class="k">array</span><span class="p">(</span>
                <span class="s1">&#39;type&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;INT&#39;</span><span class="p">,</span>
                <span class="s1">&#39;constraint&#39;</span> <span class="o">=&gt;</span> <span class="mi">5</span><span class="p">,</span>
                <span class="s1">&#39;unsigned&#39;</span> <span class="o">=&gt;</span> <span class="k">TRUE</span><span class="p">,</span>
                <span class="s1">&#39;auto_increment&#39;</span> <span class="o">=&gt;</span> <span class="k">TRUE</span>
        <span class="p">),</span>
        <span class="s1">&#39;blog_title&#39;</span> <span class="o">=&gt;</span> <span class="k">array</span><span class="p">(</span>
                <span class="s1">&#39;type&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;VARCHAR&#39;</span><span class="p">,</span>
                <span class="s1">&#39;constraint&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;100&#39;</span><span class="p">,</span>
                <span class="s1">&#39;unique&#39;</span> <span class="o">=&gt;</span> <span class="k">TRUE</span><span class="p">,</span>
        <span class="p">),</span>
        <span class="s1">&#39;blog_author&#39;</span> <span class="o">=&gt;</span> <span class="k">array</span><span class="p">(</span>
                <span class="s1">&#39;type&#39;</span> <span class="o">=&gt;</span><span class="s1">&#39;VARCHAR&#39;</span><span class="p">,</span>
                <span class="s1">&#39;constraint&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;100&#39;</span><span class="p">,</span>
                <span class="s1">&#39;default&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;King of Town&#39;</span><span class="p">,</span>
        <span class="p">),</span>
        <span class="s1">&#39;blog_description&#39;</span> <span class="o">=&gt;</span> <span class="k">array</span><span class="p">(</span>
                <span class="s1">&#39;type&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;TEXT&#39;</span><span class="p">,</span>
                <span class="s1">&#39;null&#39;</span> <span class="o">=&gt;</span> <span class="k">TRUE</span><span class="p">,</span>
        <span class="p">),</span>
<span class="p">);</span>
</pre></div>
</div>
<p>After the fields have been defined, they can be added using
<tt class="docutils literal"><span class="pre">$this-&gt;dbforge-&gt;add_field($fields);</span></tt> followed by a call to the
<tt class="docutils literal"><span class="pre">create_table()</span></tt> method.</p>
<p><strong>$this-&gt;dbforge-&gt;add_field()</strong></p>
<p>The add fields method will accept the above array.</p>
<div class="section" id="passing-strings-as-fields">
<h4>Passing strings as fields<a class="headerlink" href="#passing-strings-as-fields" title="Permalink to this headline">¶</a></h4>
<p>If you know exactly how you want a field to be created, you can pass the
string into the field definitions with add_field()</p>
<div class="highlight-ci"><div class="highlight"><pre><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">add_field</span><span class="p">(</span><span class="s2">&quot;label varchar(100) NOT NULL DEFAULT &#39;default label&#39;&quot;</span><span class="p">);</span>
</pre></div>
</div>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">Passing raw strings as fields cannot be followed by <tt class="docutils literal"><span class="pre">add_key()</span></tt> calls on those fields.</p>
</div>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">Multiple calls to add_field() are cumulative.</p>
</div>
</div>
<div class="section" id="creating-an-id-field">
<h4>Creating an id field<a class="headerlink" href="#creating-an-id-field" title="Permalink to this headline">¶</a></h4>
<p>There is a special exception for creating id fields. A field with type
id will automatically be assigned as an INT(9) auto_incrementing
Primary Key.</p>
<div class="highlight-ci"><div class="highlight"><pre><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">add_field</span><span class="p">(</span><span class="s1">&#39;id&#39;</span><span class="p">);</span>
<span class="c1">// gives id INT(9) NOT NULL AUTO_INCREMENT</span>
</pre></div>
</div>
</div>
</div>
<div class="section" id="adding-keys">
<h3><a class="toc-backref" href="#id6">Adding Keys</a><a class="headerlink" href="#adding-keys" title="Permalink to this headline">¶</a></h3>
<p>Generally speaking, you&#8217;ll want your table to have Keys. This is
accomplished with $this-&gt;dbforge-&gt;add_key(&#8216;field&#8217;). An optional second
parameter set to TRUE will make it a primary key. Note that add_key()
must be followed by a call to create_table().</p>
<p>Multiple column non-primary keys must be sent as an array. Sample output
below is for MySQL.</p>
<div class="highlight-ci"><div class="highlight"><pre><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">add_key</span><span class="p">(</span><span class="s1">&#39;blog_id&#39;</span><span class="p">,</span> <span class="k">TRUE</span><span class="p">);</span>
<span class="c1">// gives PRIMARY KEY `blog_id` (`blog_id`)</span>

<span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">add_key</span><span class="p">(</span><span class="s1">&#39;blog_id&#39;</span><span class="p">,</span> <span class="k">TRUE</span><span class="p">);</span>
<span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">add_key</span><span class="p">(</span><span class="s1">&#39;site_id&#39;</span><span class="p">,</span> <span class="k">TRUE</span><span class="p">);</span>
<span class="c1">// gives PRIMARY KEY `blog_id_site_id` (`blog_id`, `site_id`)</span>

<span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">add_key</span><span class="p">(</span><span class="s1">&#39;blog_name&#39;</span><span class="p">);</span>
<span class="c1">// gives KEY `blog_name` (`blog_name`)</span>

<span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">add_key</span><span class="p">(</span><span class="k">array</span><span class="p">(</span><span class="s1">&#39;blog_name&#39;</span><span class="p">,</span> <span class="s1">&#39;blog_label&#39;</span><span class="p">));</span>
<span class="c1">// gives KEY `blog_name_blog_label` (`blog_name`, `blog_label`)</span>
</pre></div>
</div>
</div>
<div class="section" id="creating-a-table">
<h3><a class="toc-backref" href="#id7">Creating a table</a><a class="headerlink" href="#creating-a-table" title="Permalink to this headline">¶</a></h3>
<p>After fields and keys have been declared, you can create a new table
with</p>
<div class="highlight-ci"><div class="highlight"><pre><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">create_table</span><span class="p">(</span><span class="s1">&#39;table_name&#39;</span><span class="p">);</span>
<span class="c1">// gives CREATE TABLE table_name</span>
</pre></div>
</div>
<p>An optional second parameter set to TRUE adds an &#8220;IF NOT EXISTS&#8221; clause
into the definition</p>
<div class="highlight-ci"><div class="highlight"><pre><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">create_table</span><span class="p">(</span><span class="s1">&#39;table_name&#39;</span><span class="p">,</span> <span class="k">TRUE</span><span class="p">);</span>
<span class="c1">// gives CREATE TABLE IF NOT EXISTS table_name</span>
</pre></div>
</div>
<p>You could also pass optional table attributes, such as MySQL&#8217;s <tt class="docutils literal"><span class="pre">ENGINE</span></tt>:</p>
<div class="highlight-ci"><div class="highlight"><pre><span class="nv">$attributes</span> <span class="o">=</span> <span class="k">array</span><span class="p">(</span><span class="s1">&#39;ENGINE&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;InnoDB&#39;</span><span class="p">);</span>
<span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">create_table</span><span class="p">(</span><span class="s1">&#39;table_name&#39;</span><span class="p">,</span> <span class="k">FALSE</span><span class="p">,</span> <span class="nv">$attributes</span><span class="p">);</span>
<span class="c1">// produces: CREATE TABLE `table_name` (...) ENGINE = InnoDB DEFAULT CHARACTER SET utf8 COLLATE utf8_general_ci</span>
</pre></div>
</div>
<div class="admonition note">
<p class="first admonition-title">Note</p>
<p class="last">Unless you specify the <tt class="docutils literal"><span class="pre">CHARACTER</span> <span class="pre">SET</span></tt> and/or <tt class="docutils literal"><span class="pre">COLLATE</span></tt> attributes,
<tt class="docutils literal"><span class="pre">create_table()</span></tt> will always add them with your configured <em>char_set</em>
and <em>dbcollat</em> values, as long as they are not empty (MySQL only).</p>
</div>
</div>
<div class="section" id="dropping-a-table">
<h3><a class="toc-backref" href="#id8">Dropping a table</a><a class="headerlink" href="#dropping-a-table" title="Permalink to this headline">¶</a></h3>
<p>Execute a DROP TABLE statement and optionally add an IF EXISTS clause.</p>
<div class="highlight-ci"><div class="highlight"><pre><span class="c1">// Produces: DROP TABLE table_name</span>
<span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">drop_table</span><span class="p">(</span><span class="s1">&#39;table_name&#39;</span><span class="p">);</span>

<span class="c1">// Produces: DROP TABLE IF EXISTS table_name</span>
<span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">drop_table</span><span class="p">(</span><span class="s1">&#39;table_name&#39;</span><span class="p">,</span><span class="k">TRUE</span><span class="p">);</span>
</pre></div>
</div>
</div>
<div class="section" id="renaming-a-table">
<h3><a class="toc-backref" href="#id9">Renaming a table</a><a class="headerlink" href="#renaming-a-table" title="Permalink to this headline">¶</a></h3>
<p>Executes a TABLE rename</p>
<div class="highlight-ci"><div class="highlight"><pre><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">rename_table</span><span class="p">(</span><span class="s1">&#39;old_table_name&#39;</span><span class="p">,</span> <span class="s1">&#39;new_table_name&#39;</span><span class="p">);</span>
<span class="c1">// gives ALTER TABLE old_table_name RENAME TO new_table_name</span>
</pre></div>
</div>
</div>
</div>
<div class="section" id="modifying-tables">
<h2><a class="toc-backref" href="#id10">Modifying Tables</a><a class="headerlink" href="#modifying-tables" title="Permalink to this headline">¶</a></h2>
<div class="section" id="adding-a-column-to-a-table">
<h3><a class="toc-backref" href="#id11">Adding a Column to a Table</a><a class="headerlink" href="#adding-a-column-to-a-table" title="Permalink to this headline">¶</a></h3>
<p><strong>$this-&gt;dbforge-&gt;add_column()</strong></p>
<p>The <tt class="docutils literal"><span class="pre">add_column()</span></tt> method is used to modify an existing table. It
accepts the same field array as above, and can be used for an unlimited
number of additional fields.</p>
<div class="highlight-ci"><div class="highlight"><pre><span class="nv">$fields</span> <span class="o">=</span> <span class="k">array</span><span class="p">(</span>
        <span class="s1">&#39;preferences&#39;</span> <span class="o">=&gt;</span> <span class="k">array</span><span class="p">(</span><span class="s1">&#39;type&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;TEXT&#39;</span><span class="p">)</span>
<span class="p">);</span>
<span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">add_column</span><span class="p">(</span><span class="s1">&#39;table_name&#39;</span><span class="p">,</span> <span class="nv">$fields</span><span class="p">);</span>
<span class="c1">// Executes: ALTER TABLE table_name ADD preferences TEXT</span>
</pre></div>
</div>
<p>If you are using MySQL or CUBIRD, then you can take advantage of their
AFTER and FIRST clauses to position the new column.</p>
<p>Examples:</p>
<div class="highlight-ci"><div class="highlight"><pre><span class="c1">// Will place the new column after the `another_field` column:</span>
<span class="nv">$fields</span> <span class="o">=</span> <span class="k">array</span><span class="p">(</span>
        <span class="s1">&#39;preferences&#39;</span> <span class="o">=&gt;</span> <span class="k">array</span><span class="p">(</span><span class="s1">&#39;type&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;TEXT&#39;</span><span class="p">,</span> <span class="s1">&#39;after&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;another_field&#39;</span><span class="p">)</span>
<span class="p">);</span>

<span class="c1">// Will place the new column at the start of the table definition:</span>
<span class="nv">$fields</span> <span class="o">=</span> <span class="k">array</span><span class="p">(</span>
        <span class="s1">&#39;preferences&#39;</span> <span class="o">=&gt;</span> <span class="k">array</span><span class="p">(</span><span class="s1">&#39;type&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;TEXT&#39;</span><span class="p">,</span> <span class="s1">&#39;first&#39;</span> <span class="o">=&gt;</span> <span class="k">TRUE</span><span class="p">)</span>
<span class="p">);</span>
</pre></div>
</div>
</div>
<div class="section" id="dropping-a-column-from-a-table">
<h3><a class="toc-backref" href="#id12">Dropping a Column From a Table</a><a class="headerlink" href="#dropping-a-column-from-a-table" title="Permalink to this headline">¶</a></h3>
<p><strong>$this-&gt;dbforge-&gt;drop_column()</strong></p>
<p>Used to remove a column from a table.</p>
<div class="highlight-ci"><div class="highlight"><pre><span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">drop_column</span><span class="p">(</span><span class="s1">&#39;table_name&#39;</span><span class="p">,</span> <span class="s1">&#39;column_to_drop&#39;</span><span class="p">);</span>
</pre></div>
</div>
</div>
<div class="section" id="modifying-a-column-in-a-table">
<h3><a class="toc-backref" href="#id13">Modifying a Column in a Table</a><a class="headerlink" href="#modifying-a-column-in-a-table" title="Permalink to this headline">¶</a></h3>
<p><strong>$this-&gt;dbforge-&gt;modify_column()</strong></p>
<p>The usage of this method is identical to <tt class="docutils literal"><span class="pre">add_column()</span></tt>, except it
alters an existing column rather than adding a new one. In order to
change the name you can add a &#8220;name&#8221; key into the field defining array.</p>
<div class="highlight-ci"><div class="highlight"><pre><span class="nv">$fields</span> <span class="o">=</span> <span class="k">array</span><span class="p">(</span>
        <span class="s1">&#39;old_name&#39;</span> <span class="o">=&gt;</span> <span class="k">array</span><span class="p">(</span>
                <span class="s1">&#39;name&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;new_name&#39;</span><span class="p">,</span>
                <span class="s1">&#39;type&#39;</span> <span class="o">=&gt;</span> <span class="s1">&#39;TEXT&#39;</span><span class="p">,</span>
        <span class="p">),</span>
<span class="p">);</span>
<span class="nv">$this</span><span class="o">-&gt;</span><span class="na">dbforge</span><span class="o">-&gt;</span><span class="na">modify_column</span><span class="p">(</span><span class="s1">&#39;table_name&#39;</span><span class="p">,</span> <span class="nv">$fields</span><span class="p">);</span>
<span class="c1">// gives ALTER TABLE table_name CHANGE old_name new_name TEXT</span>
</pre></div>
</div>
</div>
</div>
<div class="section" id="class-reference">
<h2><a class="toc-backref" href="#id14">Class Reference</a><a class="headerlink" href="#class-reference" title="Permalink to this headline">¶</a></h2>
<dl class="class">
<dt id="CI_DB_forge">
<em class="property">class </em><tt class="descname">CI_DB_forge</tt><a class="headerlink" href="#CI_DB_forge" title="Permalink to this definition">¶</a></dt>
<dd><dl class="method">
<dt id="CI_DB_forge::add_column">
<tt class="descname">add_column</tt><big>(</big><em>$table</em><span class="optional">[</span>, <em>$field = array()</em><span class="optional">[</span>, <em>$_after = NULL</em><span class="optional">]</span><span class="optional">]</span><big>)</big><a class="headerlink" href="#CI_DB_forge::add_column" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$table</strong> (<em>string</em>) &#8211; Table name to add the column to</li>
<li><strong>$field</strong> (<em>array</em>) &#8211; Column definition(s)</li>
<li><strong>$_after</strong> (<em>string</em>) &#8211; Column for AFTER clause (deprecated)</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">TRUE on success, FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">bool</p>
</td>
</tr>
</tbody>
</table>
<p>Adds a column to a table. Usage:  See <a class="reference internal" href="#adding-a-column-to-a-table">Adding a Column to a Table</a>.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_forge::add_field">
<tt class="descname">add_field</tt><big>(</big><em>$field</em><big>)</big><a class="headerlink" href="#CI_DB_forge::add_field" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$field</strong> (<em>array</em>) &#8211; Field definition to add</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">CI_DB_forge instance (method chaining)</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">CI_DB_forge</p>
</td>
</tr>
</tbody>
</table>
<p>Adds a field to the set that will be used to create a table. Usage:  See <a class="reference internal" href="#adding-fields">Adding fields</a>.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_forge::add_key">
<tt class="descname">add_key</tt><big>(</big><em>$key</em><span class="optional">[</span>, <em>$primary = FALSE</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#CI_DB_forge::add_key" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$key</strong> (<em>array</em>) &#8211; Name of a key field</li>
<li><strong>$primary</strong> (<em>bool</em>) &#8211; Set to TRUE if it should be a primary key or a regular one</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">CI_DB_forge instance (method chaining)</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">CI_DB_forge</p>
</td>
</tr>
</tbody>
</table>
<p>Adds a key to the set that will be used to create a table. Usage:  See <a class="reference internal" href="#adding-keys">Adding Keys</a>.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_forge::create_database">
<tt class="descname">create_database</tt><big>(</big><em>$db_name</em><big>)</big><a class="headerlink" href="#CI_DB_forge::create_database" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$db_name</strong> (<em>string</em>) &#8211; Name of the database to create</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">TRUE on success, FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">bool</p>
</td>
</tr>
</tbody>
</table>
<p>Creates a new database. Usage:  See <a class="reference internal" href="#creating-and-dropping-databases">Creating and Dropping Databases</a>.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_forge::create_table">
<tt class="descname">create_table</tt><big>(</big><em>$table</em><span class="optional">[</span>, <em>$if_not_exists = FALSE</em><span class="optional">[</span>, <em>array $attributes = array()</em><span class="optional">]</span><span class="optional">]</span><big>)</big><a class="headerlink" href="#CI_DB_forge::create_table" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$table</strong> (<em>string</em>) &#8211; Name of the table to create</li>
<li><strong>$if_not_exists</strong> (<em>string</em>) &#8211; Set to TRUE to add an &#8216;IF NOT EXISTS&#8217; clause</li>
<li><strong>$attributes</strong> (<em>string</em>) &#8211; An associative array of table attributes</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">TRUE on success, FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">bool</p>
</td>
</tr>
</tbody>
</table>
<p>Creates a new table. Usage:  See <a class="reference internal" href="#creating-a-table">Creating a table</a>.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_forge::drop_column">
<tt class="descname">drop_column</tt><big>(</big><em>$table</em>, <em>$column_name</em><big>)</big><a class="headerlink" href="#CI_DB_forge::drop_column" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$table</strong> (<em>string</em>) &#8211; Table name</li>
<li><strong>$column_name</strong> (<em>array</em>) &#8211; The column name to drop</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">TRUE on success, FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">bool</p>
</td>
</tr>
</tbody>
</table>
<p>Drops a column from a table. Usage:  See <a class="reference internal" href="#dropping-a-column-from-a-table">Dropping a Column From a Table</a>.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_forge::drop_database">
<tt class="descname">drop_database</tt><big>(</big><em>$db_name</em><big>)</big><a class="headerlink" href="#CI_DB_forge::drop_database" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$db_name</strong> (<em>string</em>) &#8211; Name of the database to drop</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">TRUE on success, FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">bool</p>
</td>
</tr>
</tbody>
</table>
<p>Drops a database. Usage:  See <a class="reference internal" href="#creating-and-dropping-databases">Creating and Dropping Databases</a>.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_forge::drop_table">
<tt class="descname">drop_table</tt><big>(</big><em>$table_name</em><span class="optional">[</span>, <em>$if_exists = FALSE</em><span class="optional">]</span><big>)</big><a class="headerlink" href="#CI_DB_forge::drop_table" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$table</strong> (<em>string</em>) &#8211; Name of the table to drop</li>
<li><strong>$if_exists</strong> (<em>string</em>) &#8211; Set to TRUE to add an &#8216;IF EXISTS&#8217; clause</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">TRUE on success, FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">bool</p>
</td>
</tr>
</tbody>
</table>
<p>Drops a table. Usage:  See <a class="reference internal" href="#dropping-a-table">Dropping a table</a>.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_forge::modify_column">
<tt class="descname">modify_column</tt><big>(</big><em>$table</em>, <em>$field</em><big>)</big><a class="headerlink" href="#CI_DB_forge::modify_column" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$table</strong> (<em>string</em>) &#8211; Table name</li>
<li><strong>$field</strong> (<em>array</em>) &#8211; Column definition(s)</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">TRUE on success, FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">bool</p>
</td>
</tr>
</tbody>
</table>
<p>Modifies a table column. Usage:  See <a class="reference internal" href="#modifying-a-column-in-a-table">Modifying a Column in a Table</a>.</p>
</dd></dl>

<dl class="method">
<dt id="CI_DB_forge::rename_table">
<tt class="descname">rename_table</tt><big>(</big><em>$table_name</em>, <em>$new_table_name</em><big>)</big><a class="headerlink" href="#CI_DB_forge::rename_table" title="Permalink to this definition">¶</a></dt>
<dd><table class="docutils field-list" frame="void" rules="none">
<col class="field-name" />
<col class="field-body" />
<tbody valign="top">
<tr class="field-odd field"><th class="field-name">Parameters:</th><td class="field-body"><ul class="first simple">
<li><strong>$table</strong> (<em>string</em>) &#8211; Current of the table</li>
<li><strong>$new_table_name</strong> (<em>string</em>) &#8211; New name of the table</li>
</ul>
</td>
</tr>
<tr class="field-even field"><th class="field-name">Returns:</th><td class="field-body"><p class="first">TRUE on success, FALSE on failure</p>
</td>
</tr>
<tr class="field-odd field"><th class="field-name">Return type:</th><td class="field-body"><p class="first last">bool</p>
</td>
</tr>
</tbody>
</table>
<p>Renames a table. Usage:  See <a class="reference internal" href="#renaming-a-table">Renaming a table</a>.</p>
</dd></dl>

</dd></dl>

</div>
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